Zigzag sewing machines



May 21, 1957 Filed Feb. 3, 1955 R. A. HAYES ET AL ZIGZAG SEWING MACHINES 16 Sheets-Sheet l May 21, 1957 R. A. HAYES ETAL ZIGZAG SEWING MACHINES 16 Sheets-Sheet 2 Filed Feb. 3, 1955 May 21, 1957 R. A. HAYES I ET AL ZIGZAG SEWING MACHINES 16 Sheets-Sheet 3 Filed Feb. 3, 1955 May .21, 1957 R. A. HAYES ET AL 2,792,797

ZIGZAG SEWING MACHINES Filed Feb. 5, 1.955 16 Sheets-Sheet 4 "R. A. HAYES ET AL.

ZIGZAG SEWING MACHINES 16 SheetsSheet 5 Filed 1955 H ll 8 IM I May 21, 1957 v R. A. HAYES ETAL 2,792,797

ZIGZAG SEWING MACHINES Filed Feb. 3, 1955 l6 Sheets-Sheet 6 FIG.6

7 1, 1957 R. A. HAYES ETAL 2,792,797

ZIGZAG SEWING MACHINES Filed Feb. 3, 1955 16 Sheets-Sheet 7 FIG] s4 y 21, 1957 R. HAYES ET AL 2,792,797 I ZIGZAG SEWING MACHINES Filed Feb. 5, 1955 l6 Sheets-Sheet 8 FIGQIO a? I I F IGJI 45, J 40 M J 37d 38 37c 21, 1957 R. A. HAYES ETAL 2,792,797

ZIGZAG SEWING MACHINES Filed Feb. 3, 1955 16 Sheets-Sheet 9 FIGJ3 FIG.I5

y 21, 1957- R. A. H/AYES ET AL 2,792,797

ZIGZAG SEWING MACHINES Filed Feb. 3, 1955 l6 Sheets-Sheet l0 May 21, 1957 Filed Feb. 5, 195

R. A. HAYES ETAL ZIGZAG SEWING MACHINES 16 shee ts-sheet 11 HUI" Huh-F HIM IIEVQH May 21, 1957 R. A. HAYES ETAL ZIGZAG SEWING MACHINES l6 Sheets-Sheet l2 Filed' Feb. 3, 1955 May 21, 1957 'R. A. HAYES ETAL 2,792,797

ZIGZAG SEWING MACHINES Filed Feb. 5, 1955 1e Sheets-Sheet 13 FIG.23

R. A. HAYES ET AL ZIGZAG SEWING MACHINES May 21, 1957 16 Sheets-Sheet 14 Filed Feb. 3, 1955 my E! 3 May 21, 1957 R. A. HAYES ETAL ZIGZAG SEWING MACHINES l6 Shets-Sheet 15 Filed Feb. 5, 1955 May 21, 1957 R. A. HAYES ET AL 2,792,797

ZIGZA'G SEWING MACHINES Filed Feb. 3, 1955 16 Sheets-Sheet l6 M l i [4 United States Patent ZIGZAG SEWFNG MACHINES Robert A. Hayes, Franklin Park, and George M. Reimer,

Elmwood Park, Ill., assignors to Union Special Machine Company, Chicago, 111., a corporation ofillinuis Application February 3, 1955, Serial No. 485,882 16 Claims. (Cl. 112-158) This invention relates to zigzag sewing machines and particularly to machines of this type which are adapted to provide a seam composed of two-thread stitches of v the 404 type through the coaction of a reciprocable needle and a four motion looper, the needle being swung back and forth across the line of feed in the course of forming zigzag stitches.

A primary purpose of the invention has been to provide a machine of the character indicated which is capable of operation at high speeds, i. e. 4500 to 6000 stitches per minute. As heretofore constructed, machines adapted to form stitches of the character indicated have not been capable of operation at speeds over 3000 stitches per minute. Other machines adapted to form zigzag lockstitches of the 304 type have been capable of: operation at speeds up to 3500 stitches per minute but the overall productive capacity of these machines is comparatively low due to the necessity of frequently replacing the bobbins in the rotary hooks. The dimensions of a rotary hook are such that a single bobbin can carry only sufficient thread to form a relatively small number of seams and the machine must then be stopped to permit the introduction of a new bobbin. Considerable time is also required for the winding of bobbins. Machines of the character contemplated by the present invention, on the other hand, utilize threads which may be supplied from large cones so that continuous operation over long periods of time is made possible and the necessity of winding bobbins is eliminated.

Factors tending to limit the speed of operation of machines heretofore available for the production of 404 type stitches of the Federal Specifications are the creation of excessive vibration and noise and the causing of excessive wear of various parts when attempts have been made to increase the speed of operation of such machines. The mechanisms employed for producing the desired stitches have been quite complicated and have involved relatively heavy moving parts that have required shifting back and forth to produce the zigzag stitch efiect.

In accordance with the present invention a relatively simple and lightweight mechanism is provided for shifting a needle bar carrier back and forth across the line of feed to bring about the production of zigzag stitches. This mechanism involves very few parts which are so mounted and connected as to require a minimum of movement in producing the desired result. Moreover, it is all enclosed within a lubricant tight housing which makes possible the effective lubrication of all wear receiving surfaces.

A special feature of the invention is the provision of an L-shaped lever, of a special, rigid but lightweight construction, which has the junction between its two branches suitably pivoted adjacent thetop of. the needle head. One leg or branch of this lever extends downwardly within the needle head and carries suitable bearin gs for the reciprocation of the needle bar therein. The other leg or branch extends substantially horizontally through the hollow overhanging arm of the frame of the 2,792,79'7 Patented May 21, 1957 machine and terminates within the top of the vertical standard of the frame. Suitable means are provided adjacent the free end of the horizontal leg of the lever to prevent whipping or lateral movement of this end. Simple connections are provided in the vertical standard for imparting rocking movements, of readily variable extent, to the lever. The location of the pivot for the lever, within the needle head, is such as to enable the use of a full length needle bar which extends outwardly from the top of. the needle head. it also brings about a desirable relation between the needle and the looper for the formation of stitches'for the two lines of reciprocation of the needle bar.

Another special feature of the invention is the provision of a particular form of cam for driving the connections which rock the L-shaped lever discussed above. This cam has only a 70 dwell portion and thus has a more gradual slope to the active portions which bring about the lateral swinging movements of the needle bar. Cams heretofore employed for a similar purpose have been provided with dwells of at least Ithas been found that a cam having only a 70 dwell greatly reduces the noise and vibration developed in operating at high speed. A dwell of 90 or more produces particularly objectionable noise and vibration when the lateral movement of the needle bar across the line of feed is relatively great, i. e. around of an inch or greater, and the machine is operated at a speed to provide more than 4000 stitches per minute.

A further special feature of the invention is the provision of an adjustable connection in the linkage connecting the above mentioned cam with the L-shaped lever which is such as to enable infinite adjustment from 0 to a predetermined maximum, say A, of the extent of lateral movement of the needle across the line of feed. Thus the machine may be adapted to produce ordinary two thread stitches of the 401 type or it may be adjusted to produce a stitch of. the 404 type having any desired spacing, within the specified limits, between the two lines along which the needle penetrates the work.

Another important feature of the invention is the provision for adequate lubrication of all of the wear receiving parts. This is made possible by the construction and arrangement of the driving connections for the various stitch forming and work feeding instrumentalities and their enclosure within lubricant tight portions of a hollow frame.

Still another feature of the invention is the provision of a top roller feed or puller mechanism and driving connections therefor which are of novel construction and arrangement. An improved, simple expedient is also provided for stripping the work from the surface of the puller roller to prevent wrapping of the work about the roller.

Other objects, features and advantages of the invention will appear from the detailed description of an illustrative embodiment of the same which will now be given in connection with the accompanying drawings, in' which:

Fig. 1 is a view, partly in elevation and partly in vertical section, of a sewing machine embodying features of the invention, certain portions of the frame being broken away and various parts being shown in section;

Fig. 2 is an end elevation of the machine, as seen from the left inFig. l, the cover plate for the needle head being removed; 7

Fig. 3 is an end view of the machine, as seen from the right in Fig. 1, portions of the frame being broken away to disclose the interior mechanism;

Fig. 4 is a top plan view of the machine with certain cover plates removed and a portion of the frame broken away;

3 Fig. 5 is a horizontal sectional view through the machine taken just beneath the cloth plate;

Fig. 6 is a view similar to Fig. 5 illustrating a slightly modified construction;

Fig. 7 is a vertical sectional view taken along the line 7-7 of Fig. 5;

Fig. 8 is a vertical sectional view taken along the line 8-8 of Fig. 5;

Fig. 9 is an enlarged vertical sectional view taken along the line 9-9 of Fig. 1;

Fig. 10 is a detail view of a rock member shown in Fig. 9, as seen from the left in said figure;

Fig. 11 is a sectional view taken along the line 11-11 of Fig. 9;

Fig. 12 is an enlarged detail view of the cam element shown in Fig. 9;

Fig. 13 is an elevational view of the front of the base portion of a modified machine adapted for production of zigzag stitches of wide gauge;

Fig. 14 is a vertical section taken along the line 14-14 of Fig. 13;

Fig. 15 is a detail view showing, in plan, certain parts disclosed in Fig. 13; i

Fig. 16 is a vertical sectional view taken along the line 16-16 of Fig. 13;

Fig. 17 is a detail view showing, in elevation, a moditbied form of L-shaped lever adapted to carry the needle Fig. 18 is an end view of the modified lever, as viewed from the left in Fig. 17;

Fig. 19 is a View of the modified L-shaped lever, as seen from the right in Fig. 17;

Fig. 20 is an enlarged vertical sectional view taken along the line 20-20 of Fig. 17;

Fig. 21 is a plan view of the lever shown in Fig. 17;

Fig. 22 is a front elevational view, with portions of the frame broken away, showing a modified form of machine including a puller mechanism;

Fig. 23 is an end view of the machine illustrated in Fig. 22, as seen from the left of the latter, certain parts being broken away and shown in section;

Fig. 24 is a horizontal sectional view taken along the line 24-24 of Fig. 22, portions being broken away for clarity of illustration of certain parts;

' Fig. 2 5 is an exploded perspective view of certain driving connections embodied in the machine illustrated in Fig. 22;

Fig. 26 is a vertical sectional view taken along the line 26-26 of Fig. 22;

Fig. 27 is a vertical sectional view taken along the line 27-27 of Fig. 24;

Fig. 28 is an enlarged sectional view taken along the line 28-28 of Fig. 27;

Fig. 29 is a plan view of a member secured to the presser bar of the modified machine shown in Fig. 22;

Fig. 30 is a sectional view through the puller roller of the modified machine; and

Fig. 31 is a front elevational view of the puller roller and related parts.

Referring now to the drawings, the illustrative embodiment of the invention shown in Figs. 1 to 5, inclusive, comprises a frame having a work supporting base portion 10, a vertical standard 11 rising from the right end of the base, and an overhanging arm 12 extending laterally from the upper end of the standard and terminating in a needle head 13. A main drive shaft 14 extends longitudinally of the base and is journaled in suitable bearings provided therein. It projects outwardly from the frame at the right end thereof (Fig. 1) and carries at its outer end a combined handwheel and pulley 15. For convenience 70 in assembling the shaft .14 in the frame, the shaft is divided into several sections which are interconnected by couplingsl6 and 17.

Within the needle head there is mounted a vertically needle 19. The needle bar is mounted in bearings 20 and 21 carried by a vertically disposed rock frame 22 which is pivoted upon a stud 23 carried by the needle head. Stud 23 is positioned adjacent the top of the needle head and at a point adjacent the path of travel of the needle bar but on that side of the latter which is away from the vertical standard. This arrangement of the stud enables the use of a full length needle bar which extends upwardly through the top of the needle head and may suitably carry a thread take-up arm or eyelet at its upper end. It also causes the needle 19 to assume advantageous positions in relation to the complementary stitch forming means as the frame 22 is rocked about the pivot 23, in the manner to be explained, for the purpose of producing zigzag stitches. Bearing 20 is preferably provided with a plurality of grooves 20a extending circumferentially about the surface of the needle bar.

' Similarly, the bearing 21 is preferably provided with a spiral groove 21a in the wall which surrounds the needle bar. These grooves assist in retaining lubricant within the bearings. Secured to the frame 22 is an elongated arm 24 which extends longitudinally through the overhanging arm of the frame. Members 22 and 24 are rigidly interconnected by means of rivets 25 or the like to form, in effect, an L-shaped lever. At the end of the arm 24 which extends into the hollow vertical standard, adjacent the top of the latter, there is carried a ball-pin 26 having a reduced shank 26a inserted in an opening in the arm 24 and secured therein by means of a set-screw 27. Cooperating with the ball stud 26 is a strap 28 at the upper end of a pitman 29 which has at its lower end another strap 30 cooperating with a ball pin 31 adapted to be secured, in any suitable position of adjustment, along an arcuate slot 32 formed in an upwardly extending portion of a rock member or frame 33 journaled upon a stud 34 within the vertical standard. Pitman 29 is preferably of an extensible character and for this purpose may be formed of a plurality of screw threaded rods 29a and 29b which are coupled by an internally threaded sleeve 290. The threads at the lower end of rod 29a and at the upper end of rod 29b are of opposite hand so that upon turning of the sleeve 290 the two rods may be either drawn together or urged apart. A nut 29d serves to lock the parts in adjusted position. The rock frame 33 has a forked lower end 35 (Figs. 3 and 9), the two branches of the fork being provided on their inner faces with steel plates 36, formed preferably of clock spring steel, which cooperate with a cam 37 secured to a stub shaft 38. The branches of the forked portion 35 of the rock frame are sufficiently resilient to permit the same to be drawn together by means of a bolt 39 to insure a desired close lit in relation to the cam 37. Stud 34 and stub shaft 38 are fixedly mounted in a bracket 40 (Figs. 3, 5, and 11). This bracket has a base 41 secured by screws 42 to a plate 43 fitted over an opening in the front wall of the vertical standard and secured thereto by means of screws 44.

Mounted on a hub extension of the cam 37 and suitably secured to the latter is a gear 45 preferably formed of fibrous material to reduce noise and vibration. Gear 45 meshes with a pinion 46 secured to the shaft 14 within the vertical standard. The gear is of twice as great a diameter as the pinion 46 so that the cam 37 will be given only one revolution for two revolutions of the shaft 14. It will be apparent that as the shaft 14 is rotated the connections described will cause oscillation of the L-shaped frame 22, 24 about the pivot 23 and thus shift the path of the needle 19 successively back and forth in adirection transverse to the line of feed of the work into two alternate positions. As best shown in Fig. 12, the cam 37 is preferably provided with arcuate dwell portions 37a and 37b, eachof which extends over an arc of '7( The intermediate portions 370 and 37d cause the shifting of the L-shaped'frame inthe manner exreciprocable needle bar 18 carrying at its lower end a plainedl Heretofore, eccentrics provided in zigzag sewall ing machines for causing a lateral movement of thejneedle bar across the line of feed have been provided with 90 dwell portions. It has been found, however, that dwells of 70 are adequate to enable the needle to penetrate the work and pass below the throat plate of the work support and to be retracted to a position above the work. It has been found also that by limiting the dwell portions of the cam to 70, and thus increasing the extent of the periphery of the cam which is effective in shifting the needle bar frame, there results a substantial reduction in the noise and vibration produced in operating the machine at high speeds. This becomes particularly important when the throw of the needle across the line of feed is relatively great, i. e., A; of an inch or greater. The eccentricity of the cam 37 may suitably be .092, .125 or .160 for lateral movements of the needle up to A3, A or /4", respectively.

It should be understood that the slot 32 (Fig. 3) is arcuate and is curved about the axis of the ball pin 26. Moreover, as shown, the slot 32 extends to a point sub stantially in vertical alignment with the pivot 34 so that the ball pin 31 may be shifted to such a position. When so shifted no appreciable rocking movement will be imparted to the L-shaped frame 22, 24.

For reciprocating the needle bar 13 the shaft 14 is provided with a crank 47 which is preferably of the form disclosed in the Attwood application, Serial No. 310,295, filed on September 18, 1952. The crank element coopcrates with a strap 48 carried by the lower ends of a pair of pitman rods 49 which at their upper ends carry another strap 50 arranged to cooperate with a ball pin 51 extending from the end of a needle lever 52 rockably mounted by means of a shaft 53 extending transversely of the overhanging arm. At its opposite end the needle lever is connected by a link 54 with a clamping element 55 secured to the needle bar 18. Through the connections described the needle bar will be reciprocated upon each revolution of the shaft 14 and the needle 19 will be carried through the Work and one or another of two apertures in the throat plate, depending upon the position of the cam 37 in its cycle of operation.

Cooperating with the needle beneath the throat plate is a four-motion looper 56 suitably mounted on the upper end of an arm 57 which is rockable about a pivot stud 58 projecting forwardly from a sleeve 59. This sleeve is secured to a rock shaft 60 suitably journaled in the base of the frame. As best shown in Fig. 8, an arm 61 clamped upon the rock shaft 60 is pivotally connected with the lower end of a strap 62 which cooperates with an eccentric 63 secured to the shaft 14. Suitable needleavoid movements are imparted to the looper upon the rocking of the shaft 60 through the connections described. Loop-seizing and loop-shedding movements are imparted to the looper by means of a pitman 64 (Figs. 1 and 5) having a strap 65 at one end cooperating with a ball pin 66 extending forwardly from the looper carrier 57. At its opposite end the pitman 64 is provided with a strap 67 which cooperates with a ball pin 68 projecting laterally from an arm 69 secured to a rock shaft 70 mounted in suitable bearings on the frame. The inner or rearward end of the shaft 70 is enlarged, as indicated at '71 in Figs. 5 and 7. A radially extending stud 72 has screw threaded engagement with the enlarged portion 71 of the shaft and carries a ball pin '73 at its outer end cooperating with a strap at the lower end of a pitman 74 whose upper end carries a strap cooperating with a spherical crank element 75 provided on the shaft 14 (Figs. 1 and 7). it will be understood that the timing of the operation of the various stitch forming instrumentalities is so synchronized that upon each revolution of the main shaft 14 a so-called two-thread chain stitch will be produced. Moreover, due to the swinging of the L-shaped frame 22, 24 back and forth across the line of feed upon each two revolutions of the shaft 14 the line 6 of stitching produced will provide a zigzag effect along the surface of the work.

For advancing work between successive stitches a fourmotion feed dog 76 is provided (Figs. 2 and 5). This feed dog is adjustably mounted in a suitable manner at the forward end .of a feed bar 77, the rear end of which is rockably mounted, by means of a pivot pin 78, on a feed rocker 79. The latter is carried by a shaft 80 supported by the base portion of the frame. For imparting rocking movements to the feed rocker '79, the latter is provided with a laterally extending stud Sllcrto which is clamped the rearward end of an arm 81. The forward end of this arm is pivotally connected with a pitman 82 having a strap portion cooperating with an adjustable eccentric 83. Through the connections described work advancing and return movements are imparted to the feed dog. Lifting and lowering movements are imparted to the feed dog in a well known manner by connections from an eccentric 84 (Fig. 1) carried by the shaft .14.

Cooperating with the feed dog in advancing the work is a presser foot 85 which is preferably pivotally mounted upon a shank element 86 clamped upon the lower end of a presser bar 87. This bar is suitably mounted for vertical or axial movement in bearings 88 and 89 carried by the needle head. A spring 90 surrounding the presser bar urges the latter downwardly to retain the presser foot in engagement with the work. To enable the presser bar to be lifted manually or under knee or foot control, there is secured to the bar (Fig. 2) a block 91 which is connected by a link 92 with a lever 93 mounted on a pivot screw 95 Within the overhanging arm of the frame. An upwardly extending arm 94 of the lever is connected by a rod 96 with a plate 97 secured to a rock shaft 98 journaled in the rear wall of the vertical standard. Any suitable connections, such as those disclosed in the patent to Peterson, et al., No. 2,598,426, granted May 27, 1952, may be provided for rocking the shaft 98 under control of a knee press or foot treadle or the like. The connections may comprise an arm 99 secured to the shaft 98 (Figs. 2, 3 and 4) and having its free end connected by a chain or rod with a knee press or the like. The arm 99 may also operate a thread tension releasing mechanism. For this purpose a downward extension 9941 of the arm may have an elongated camming slot cooperating with a screw stud 100 projecting from an arm 101 clamped upon a rock shaft 102 which extends through the vertical standard from the rear to the front thereof. At its forward end the shaft 102 carries an arm 103 having a pin 104 which acts upon a plate 105, by a camming action or the like, to perform the thread tension releasing function upon the thread tension devices 106 and 107.

Referring now to Fig. 6 there is shown a slightly modified construction which differs from the embodiment of Figs. 1 to 5 inclusive, only in the form and arrangement of the devices for imparting the needle avoid movements to the looper. As shown in Fig. 6, the sleeve 59 upon which the looper carrier is pivotally mounted is secured to a rock shaft 60:: which extends into a lubricant retaining chamber 108 provided in the center region of the base of the frame. The devices for rocking the shaft are disposed within this lubricant chamber. They are similar to the devices employed for rocking the shaft 60 as illustrated in Fig. 8. Thus an eccentric 109 similar to eccentric 63 is secured to the shaft 14 and has cooperating therewith a pitman 110, the lower end of which is pivotally connected with an arm 110a secured to the shaft 60a.

In Figs. 13 to 16 inclusive, there is illustrated a modification which embodies a four-motion loop retainer 111. It is desirable to employ such a retainer whenever a relatively wide gauge zigzag stitch is to be produced. This retainer serves to hold the needle thread loop well back on the looper so as to position the thread triangle for proper entry by the needle upon its next descent 7 through the throat plate. This is particularly desirable when the needle bar carrying frame is in its right hand position (Fig. l). The mounting and operating connections for'the loop retainer 111 are such as to impart to the free end of the retainer an elliptical path such as indicated at 112 in Fig. 15. For this purpose the retainer 111 is retained in an opening 113 in a block 1114 secured to-the upper surface of a pitman 115 which cooperates with an eccentric 116 secured to the shaft 14. Pitman 115 has a forked extension arranged to cooperate with the rock shaft 611 for sliding movement in relation to thelatter. It will be apparent that the cocentric 116 imparts to the retainer the component of its movement which is in the direction of feed. For imparting a component of movement to the retainer in a direction transverse to the line of feed a spherical eccentric 117 is secured to the shaft 14 and cooperates with a strap 1187on a pitman 119. The latter has a strap 120 at its opposite end which cooperates with a ball pin 121 projecting laterally from a sleeve-like member 122 which is oscillatably mounted on a fixed stud or bolt 123. A laterally extending sleeve-like portion 124 of the member 122 is arranged to receive telescopically a pin 125 secured to a strap 126 which cooperates with a ball pin 127 secured to and extending downwardly from the pitman 115. It will be apparent that through the connections described the pitman 115 will be shifted back and forth across the cylindrical surface of the eccentric 116. The two eccentrics 116 and 117 will accordingly impart to the loop retainer the elliptical motion hereinabove mentioned.

When the loop retainer is provided the arrangement disclosed in Fig. 6 for imparting needle avoid movements to the looper should be employed to provide room for the extra eccentrics described above. If desired the eccentric for rocking the shaft 60 may be incorporated in one of the couplings which join the several sections of shaft 14. Thus, as shown in Fig. 13, a combined coupling and eccentric 16a may be provided, this serving to rock the shaft 611 by connections similar to those shown in Fig. 8.

Referring next to Figs. 17 to 21 inclusive, there is illustrated, in detail, the construction of a modified and, in fact, preferred form of L-shaped lever adapted to carry the needle bar and to swing the latter transversely across the line of feed. The modified lever is of lightweight but sturdy construction. It has been found to have less tendency to flex and become distorted, during rapid operations of the machine, than a lever of heavier construction. In this preferred form the lever comprises a pair of L-shaped frames or plates 128 and 129 which are preferably formed of relatively thin sheet steel. These plates or frame pieces are stiffened and united to form a unitary structure by a series of blocks. Thus a block 130 is inserted between the two frame pieces at the lower end of the vertical leg of the lever. This block is preferably formed of ductile cast iron and is copper welded to the two frame pieces. By the employment of ductile cast iron in the production of the block 131), and other of the blocks to be described, various advantages are obtained. In the first place it enables the copper welding of the pieces to form the unitary structure; secondly, ductile cast iron has good bearing and machining qualities.

As best shown in Fig. 20 the block 130 is provided with a centrally disposed bore or passageway extending through the same from top to bottom for the reception of the needle bar. Intermediate its ends the bore is slightly enlarged for clearance purposes in the area designated 132. Adjacent the upper end of the bore there is provided a pair of annular grooves 133 of frusto-conical form for the purpose of retaining lubricant for the needle bar within the bore of the block.

Atthe elbow of the L-shaped lever there is provided an L-shaped block 134 also preferably formed of ductile cast iron and copper welded to the two side frames 128 ea/nae and 129. The block 134 is provided with a transversely extending aperture 135 which is aligned with corresponding apertures through the side frames 128 and 129 for the reception of the .pivot pin 23 (Fig. 1). This aperture 135 is disposed toward the left side (Fig. 17) of a vertical bore or opening 136 which extends through the block 134. It will be understood that the bore or opening 136 is adapted to receive and provide a bearing surface for the needle bar adjacent the upper end of the latter. The configuration of the bore 136 is preferably as shown and its upper portion is preferably provided with a spiral groove 137 for lubricant retaining purposes.

At several spaced points along the horizontally disposed leg of the lever, reinforcing or stiffening blocks 138 and 139 are provided, these being copper welded to the side frames 12% and 129. At the outer end of the horizontal leg of the lever a block 140 of ductile cast iron is similarly copper welded to the plates 128 and 129. This block is provided with a longitudinally extending opening 141 arranged to receive the shank 26a of the ball pin 26 (Fig. 1). Set screws 142 are provided for retaining the ball pin within the block.

In the use of either of the forms of L-shaped lever disclosed, respectively, in Figs. 1 to 5 inclusive and in Figs. 17 to 21 inclusive, it is desirable to provide guide means adjacent the free end of the horizontally extending arm of the lever. It has been found that in the absence of such guides the long arm of the lever has a tendency to whip laterally as it is oscillated at high speed'by the connections described.

As best shown in Figs. 1, 3 and 4, the guide means may suitably comprise a plate 143 disposed horizontally across the top of the lever and secured to suitable lugs on the frame by means of screws 144. These screws cooperate with notches in the ends of the plate and allow for some adjustment of the position of the latter from front to rear of the machine frame. The plate 143 is provided with an outwardly and downwardly projecting extension 145, the vertical portion of which is closely adjacent to the front face of the arm 24 of the lever. An angle member M6 secured by a screw 147 to the top of the projection 145 provides a similar guide surface closely adjacent to the rear face of the arm 24 of the lever. Screw 147 cooperates with an elongated opening through the horizontal leg of the angle member 146 to provide for suitable adjustment. This arrangement permits proper clearance to be provided between the guide surfaces and the outer faces of the arm 24 of the lever to enable free rocking movement of the lever, but the latter is suitably confined and restrained against any lateral whipping action. It will be understood that the downwardly extending arm 22 of the L-shaped lever is suitably confined against lateral movement, both adjacent its lower end and adjacent the pivot stud 23, by cooperating surfaces on the needle head.

In Figs. 22 to 31 inclusive, there is disclosed a machine having the zigzag stitching mechanism described above and having a top feed roller or puller roller arranged to assist in advancing the work. This roller, in the illustrated embodiment, is directly in rear of the path of reciprocation of the needle. If desired, the feed roller may be located more forwardly, i. e. with its axis substantially in the transverse plane of movement of the needle bar and to one side of the path of the needle bar. The machine illustrated in Figs. 22 to 31 inclusive, embodies all of the mechanism provided in the machine illustrated in Figs. 1 to 5 inclusive. it may also embody the modifications described above in relation to other figures. The following description will be confined to the feed roller or puller roller and the mechanism for driving the same.

The feed roller is driven by connections from the gear 46 on the main shaft 14 which, as explained above, serves to drive the mechanism for shifting the needle bar transversely across the line of feed. This gear also meshes with a gear 150, preferably a fibre gear, which in turn meshes with a pinion 151 secured to a shaft 152, jour- 

